A　series　of　covalently　bound　albumin　(bovine　serum　albumin　(BSA)　and　human　serum　albumin　(HSA))　conjugates　of　phthalocyanines　functionalized　with　carboxyls　were　prepared　and　resulted　in　amide　bonds.　The　phthalocyanines　are　tetraα　(4-carboxyl　phenoxy)　phthalocyanine　zinc　(1)　and　tetra-α-[4-(2-carboxyl　pethyl)　phenoxy]　phthalocyanine　zinc　(3)　as　well　as　their　corresponding　tetra-β-substituted　counterparts　(compounds　2　and　4).　The　spectroscopic　properties　of　these　phthalocyanines　and　their　bioconjugates　in　phosphate　buffer　saline　solution　(PBS)　were　investigated.　The　phthalocyanines　that　are　covalently　bound　to　the　albumins　have　a　more　obvious　monomeric　absorption　characteristic　than　the　corresponding　free　phthalocyanines.　Moreover,　the　spectroscopic　characteristics　of　the　phthalocyanines　in　the　bioconjugates　are　not　affected　by　solution　pH.　The　substitution　position　of　the　carboxy　moieties　on　the　phthalocyanine　ring　has　an　effect　on　the　spectroscopic　transformation　of　these　macromolecules　after　conjugation　with　the　albumins.　Substitution　at　the　αposition　of　the　phthalocyanine　ring　leads　to　more　prominent　spectroscopic　changes　than　that　at　the　βposition.　Both　1-albumin　and　3-albumin　in　PBS　show　monomeric　phthalocyanine　spectra　with　Q-band　maxima　at　about　697　nmand　706　nm,　respectively.　©　Editorial　office　of　Acta　Physico-Chimica　Sinica.